In the past, Hong Kong's education system was closely similar to the system in UK. Nowadays, Hong Kong's education system has changed. Under the new system, students now are facing the 334 system.
I found a video in youtube.
From my perspective, the old system is quite stressful for students because we need to pass two public examinations to get in to University. It actually is difficult and stressful for students. For the new one, as I just experienced the old one, I don't know much about the new system. Therefore I cannot compare the pros and cons of the two systems.
However, I believe Hong Kong's education system will be much better in the future no matter in students' eyes or the whole system.